I have one that I use on my 11 Pro (not the Max); seems pretty straightforward and safe. All I have done with it though is to back up all my photos. I had hoped to be able to use it to back up some MP3 files but it doesn't seem as though that access is possible.
i hate it. I was expecting it to work the way a normal flash drive with the dongle connected would work but nope. Rather than direct access from files, everything is done through an app. In the app I tried many things but cannot make folders and when you export to the app, the option to make a folder comes up, but the keyboard does not pop up which makes it impossible to name a folder without a bluetooth keyboard
This seemed like a good alternative but with Cloud options like Mega.nz offering 50GB free or paying for iCloud storage - if you're within the ecosystem then what's NOT to use that? At least folders and files can be renamed.